Oxotremorine sesquifumarate is primarily used in research settings to study the cholinergic system, particularly in the context of neurological and pharmacological studies. It acts as a muscarinic acetylcholine receptor agonist, making it valuable for investigating the role of these receptors in various physiological processes. This compound is often employed in experimental models to mimic the effects of acetylcholine, helping researchers understand conditions like Alzheimer's disease, Parkinson's disease, and other disorders related to cholinergic dysfunction. Additionally, it is utilized in studies exploring cognitive functions, memory, and learning, as well as in the development of potential therapeutic agents targeting muscarinic receptors. Its application extends to behavioral studies in animal models to assess the impact of cholinergic activation on motor and cognitive behaviors.